Effect of heat on skin and urinary nitrogen losses: Eight young men were given an egg and milk formula at 0.7 g/kg/day level. They were exposed to heat (34-37 degrees C) daily for 7 or 7 1/2 hours for 16 days to 21 days, and N balance studies including skin-sweat N losses were conducted. The N balances were repeated with the same subjects under a cool condition (22-26 degrees C) during a period of 15 to 21 days. It was found that skin-sweat N losses were significantly higher during the hot period(s) than during the cool period. Urinary N losses were significantly lower during the hot period as compared with those of the cool period. Integumental nitrogen losses of young Chinese men: Data on scalp hair N, skin-sweat N, Nail N and N in mouth washing water etc. have been accumulated. The ratio of the nitrogen maintenance requirements to the total obligatory nitrogen losses in young men: Nitrogen maintenance requirements (including requirements for cutaneous losses) were measured in 6 men with a steamed egg formula. The figure obtained by extrapolation was 39 percent higher than the total obligatory N losses.